Frank



F. O. HOAGLAND.

LIMIT GAGE.

APPLICATION FILED JAN. 19: IQIB 1,323,280. Patented Dec. 2,1919.

lA/l/E/VTOR F/mh 0.

BY A To IVEY UNITED STATES PATENT OFFICE.

FRANK 0. HOAGLAND, OF HARTFORD, CONNECTICUT, ASSIGNOR T0 PRATT & WHITNEY COMPANY, OF NEW YORK; N. Y., A CORPORATION OF NEW JERSEY.

LIMIT-GAGE.

To all whom it may concern Be it known that I, FRANK O. HOAGLAND, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Limit- Gages, of which the following is a specification. 4

As heretofore commonly constructed, limit and other gages have been forged or other wise formed from solid metal. Gages of this type are entirely satisfactory in small sizes but for the larger sizes they are open to objection because of the relatively great weight which is necessary in order to provide the required strength and rigidity. The principal object of the present invention is to provide a gage which can be constructed in large sizes and which will have the required strength and rigiditywithout having the excessive weight which has heretofore been deemed necessary. This object I attain by making the body part of the gage tubular in form in order to provide the maximum strength in proportion to the weight. Another object of the invention is to provide improved means for mounting and securing the measuring contacts. Further objects of the invention will be apparent from the folowing specification and claims.

In the -accompanying drawing I have shown the embodiment of the invention which I now deem-preferable, but it will be understood that various modifications and substitutions of equivalents can be made without departing from the spirit of the invention as set forth in the claims appended to this specification.

Of the drawing:

Figure 1 is a plan view of a gage embodying the invention.

Fig. 2 is a side view with a part broken away.

Fig. 3 is a front view.

Fig. 4 is a sectional View on an enlarged scale taken along the line H of Fig. 1, and securing de the measuring contacts vices therefor being removed.

Fig. 5 is a view similar to Fig. 4, showing one of the measuring contacts and the,corresponding securing devices in place.

Referring to the drawing, 1 represents the main body ofthe gage which is constructed from a metallic-tube.- The tube is bent into a U-shaped form, as shown, and it is fiat- Specifieation of Letters Patent.

Patented Dec. 2, 1919.

Serial No. 212,596.

tened at opposite sides to provide flat walls 2 and 3. Except at the ends, the metal of the tube extends in uniform semi-circular curves between the flat walls 2 and 3, thus providing an oblong cross section with rounded ends. At its ends the tube has two straight sections which are parallel and which have opposed inner flat walls 4 and 5 extending perpendicularly between the walls 2 and 3 thus providing a rectangular cross section. The outer wall of each end section of the tube is preferably bent inward to form a recess as indicated at 6' in Fig. 4. The ends of the tubular body are closed, preferably by means of flat plates 7 and 8 which are held in place in any suitable manner, as for instance by a brazing. The edges of the plates 7 and 8 are rounded to elimi 'n'ate sharp corners or angles.

Carried by the parallel end sections of the gage body are pairs of opposed measuring contacts. As illustrated, there are three such pairs 9, 9, 10, 10 and 11, 11. For each pair of contacts the inner and outer walls of the body at 4: and 6 are provided with alined apertures 12 and 13. smooth and each aperture 13 is slightly larger than the corresponding aperture 12 andis suitably threaded. Each measuring contact has a main cylindrical part, which closelyfits the aperture 12, and an enlarged outer threaded part which fits the threaded aperture 13. Each contact has a slot 14 or other means permitting it to be readily turned. Bymeans of a screw driver fitting the slot, themeasuring contact can be ad justed to any desired position. For locking each contact in adjusted position I provide a screw 15 which extends through apertures 16 and 17 in the side walls 2 and 3. The enlarged head of the screw fits the larger aperture 16 and the smaller threaded end of the screw fits the aperture 17 which is suitably threaded. The head of the screw is provided with a curved annular Each aperture 12 is surface which is adapted to press against and fit the cylindrical part of the corresponding measuring contactand thus when the pieces to be gaged may be over size. The two inner contacts are adjusted so that their inner measuring surfaces are at a slightly less distance apart, this lesser distance corresponding to the permissible amount which the pieces to be gaged may be under size. In the drawing these differences in distance are greatly exaggerated in order that they may be clearly seen. In use, the piece being gaged, in order to be acceptable, must permit the outer contacts to pass, but must not permit the inner contacts to pass. The central contacts may or may not pass, and these are primarily useful for setting the machine at exactly the correct adjustment.

While it is desirable to provide means whereby the gage may be adjusted for different sizes of work or for different limits, it is nevertheless essential that the gage be not changed by the workman who is using it or by' any other unauthorized person. i To prevent such unauthorizedadjustment of the gage, I preferably fill the space at the outer ends of the measuring contacts with sealing wax, as indicated at 18. This sealing wax is molded to conform to the general outer contour of the body part of the gage and it therefore serves to provide a smoothoutline as well as to prevent adjustment. Ifdesired', the sealing wax may be impressed with a suitable seal which must be destroyed before any adjustments can be made. It will be clear that when adjustments are necessary the sealing wax is removed and the adjustments made by loosening the screws 15 and turning the contacts. After adjustment, the screws 15 are tightened and-new sealing wax is put in place and impressedwith the seal.

Vhat I claim is:

1. A gage comprising in combination a tubular U-shaped body having a uniform oblong cross section with rounded ends throughout the curved portions thereof and having a rectangular cross section at the straight parallel end portions thereof, and opposed measuring contacts carried directly by the body at the said rectangular and parallel end portionsthereof.

2. A gage comprising in'combination a tubular U-shaped body, plates covering the ends of the body, and opposed measuring contacts carried directly by the body inde pendently of the plates.

3. A gage comprising in combination a U- shaped body which is tubular in form with thin walls in order to have the maximum strength in proportion to its weight, and opposed measuring contacts carried directly by the body at the opposite end portions thereof and extending through alined apertures in the inner and outer walls of the said end portions.

4:. A gage comprising in combination a U- shaped body which is tubular in form with thin walls in orderto have the maximum strength in proportion to its weight, and opposed measuring contacts carried directly by the body at the opposite end portions thereof and extending through alined apertures inthe inner and outer walls of the said end portions, each of the said contacts being rotatable and having threaded engagement with one wall and slidable engagement with the other wall. i

5. A gage comprising in combination a U-shaped body which is tubular in form with thin walls in order to have the maximum strength in proportion to its weight, opposed measuring contacts carried directly by the body at the opposite end portions thereof and extending through. alined apertures in the inner and outer walls of the said end portions, each of the said contacts being rotatable and having threaded engagement with one wall'and slidable engagement spectively adjacent the measuring contacts and extending through alined apertures in the side walls of the said end portions of the body, each screw having threaded engagement with one wall and slidable engagement with the other wall.

6. A gage comprising in combination a tubular U-shaped body, andopposed rotatable measuring contacts extending through alined apertures in the inner and outer walls of the body and having threaded engagement respectively with'the outer walls, the said outer walls being bent inward to form recesses adapted to retain bodies of sealing wax which cover the ends of the measuring contacts and prevent the contacts from being turned.

In testimony whereof, I hereto afiix my signature.

FRANK o. HOAGLAND.

- with the otherwall, and locking screws re- 

